In shuttleless looms, that is, those looms in which weft yarn is supplied from a stationary source located outside the lateral limits of the warp yarns, it is customary to insert each pick of weft by means of a reciprocating inserter or inserters. In the most common shuttleless loom operation a supply of weft is located adjacent the right hand side of the loom and each pick of weft is drawn from the source and inserted into the shed formed between the warp yarns. The insertion itself is effected by means of an inserter carrier which is moved into and from the shed by means of a reciprocating inserter. In this usual form the inserter carrier is met at approximately the center of the warp shed by an extending carrier which grasps the weft being inserted and draws it to the other side of the loom. The extending carrier is moved into and out of the shed by means of a reciprocating inserter in the same manner in which the inserter carrier is moved.
There are two basic weft insertion methods that are used with looms of the type mentioned above. These weft insertion methods are the Gabler and Dewas methods and are frequently referred to as the "hair pin" and "gripper" methods respectively. In the Gabler insertion method a weft yarn end is held clamped outside of the selvedge after cutting and the inserting carrier then pulls a quantity of yarn from the yarn package so that a loop of yarn is initially formed in the warp shed. After a predetermined length of time, the clamped end is released so that the extending carrier can continue to draw the looped yarn to the other side of the loom. By way of contrast the Dewas system utilizes inserting and extending carriers in which the end of the yarn is gripped by the inserting carrier and then this same gripped end is transferred to the extending carrier and drawn on to the other side of the warp.
With the development of multi-color looms the various yarns have been frequently guided by a slot located in the rear wall of the carrier, this slot beginning in the upper surface of the rear wall and extending downwardly toward the bottom of the carrier and rearwardly toward the end of the carrier which is attached to the inserter member. In addition a small yarn guiding or trapping hook was used which extended generally upwardly and rearwardly with respect to the back surface of the rear wall to aid in maintaining the yarn within the guide slot.
When weaving certain types of fabrics, particularly that of high sley, such as poplin or broad cloth is not uncommon for some warp yarns to knit or in other words to fully close during harness shedding. Unfavorable conditons of this nature can be attributed to warp yarn preparation wherein slubs and other impurities are caused to adhere to the warp yarns during the preparatory stages. Imperfections of this nature very often cause certain warp yarns to knit or stitch together and present an obstructed shed into which the filling carriers enter. Additionally one or more of the warp yarns might be improperly tensioned permitting it to hang down into that area of the shed where the carrier must normally travel. In many cases filling carriers which enter sheds of these types will cut the warp yarns obstructing their path of travel and cause interruption of loom operation. In addition, carriers of the type referred to above that are used for multi-color weaving tend to be structurally weaker than those normally used in single color operation due to the fact that more of the material has been removed from the back wall to accommodate yarn reception and guiding into the carrier. In many cases actual breaking of carriers has occurred during operation and this, like yarn breakage causes loom interruption.